我需要建议：小内存占用linux邮件服务器与垃圾邮件过滤

目前的设置如下：

> Postfix提示邮件,用户在虚拟表中,存储在MySQL中
>在连接上,所有服务器都使用针对某些DNSBL的policyd-weight服务进行测试
>所有邮件都是在垃圾邮件客户端的帮助下通过SpamAssassin垃圾邮件运行的
>然后邮件随Dovecot 2’LDA(本地传递代理),虚拟用户一起提供

如你所见……

>没有病毒扫描程序运行,这是有原因的：clamav会占用所有可能的内存,而且,这个设置都会过滤掉病毒邮件(我已经使用ClamAV启用了1.5年的同样的测试,没有病毒邮件甚至连ClamAV)
>我不使用amavisd,我真的不想.如果你有足够的内存和大量的同步扫描仪,你只需要那个怪物.用手微调也是一场噩梦.
>我在postfix中运行policyd-weight而不是policyd和本地DNSBLs.我不喜欢派人离开,因为他们列出了一项服务.

重要声明：一切正常.我收到的垃圾邮件数量非常少,几乎从未得到过误报,而且大多数不良邮件都被policyd-weight所阻止.我觉得服务的唯一“问题”总共使用了很多内存.

我已经削减了spamassassin的模块(见下文),但我真的很想听到一些建议如何尽可能减少内存占用,主要是：SpamAssassin真正需要什么插件以及或多或少无用的插件,关于我目前的后缀& policyd-weight设置？

SpamAssassin规则也使用sa-compile编译(sa-update每周从cron运行一次,编译后立即运行)

这些是可能重要的一些当前配置,请告诉我您是否还需要更多.

postfix / master.cf(仅限部分)

dovecot   unix  -       n       n        -      -       pipe
  flags=DRhu user=vmail:vmail argv=/usr/bin/spamc -e /usr/lib/dovecot/deliver -d ${recipient} -f {sender}

postfix / main.cf(仅限部分)

smtpd_helo_required = yes
smtpd_helo_restrictions = permit_mynetworks,reject_invalid_hostname,permit

smtpd_recipient_restrictions =  permit_mynetworks,permit_sasl_authenticated,reject_non_fqdn_hostname,reject_non_fqdn_recipient,reject_unknown_recipient_domain,reject_unauth_pipelining,reject_unauth_destination,check_policy_service inet:127.0.0.1:12525,permit

policyd-weight.conf(仅限部件)

$REJECTMSG = "550 Mail appeared to be SPAM or forged. Ask your Mail/DNS-Administrator to correct HELO and DNS MX settings or to get removed from DNSBLs";

$REJECTLEVEL = 4;
$DEFER_STRING = 'IN_SPAMCOP= BOGUS_MX=';
$DEFER_ACTION = '450';
$DEFER_LEVEL  = 5;
$DNSERRMSG = '450 No DNS entries for your MTA,HELO and Domain. Contact YOUR administrator';

# 1: ON,0: OFF (default)
# If ON request that ALL clients are only checked against RBLs
$dnsbl_checks_only = 0;

# 1: ON (default),0: OFF
# When set to ON it logs only RBLs which affect scoring (positive or negative)
$LOG_BAD_RBL_ONLY  = 1;

## DNSBL settings
@dnsbl_score = (
        # host,hit,miss,log name
        'dnsbl.ahbl.org',3,-1,'dnsbl.ahbl.org','dnsbl.njabl.org','dnsbl.sorbs.net','bl.spamcop.net','zen.spamhaus.org','pbl.spamhaus.org','cbl.abuseat.org','list.dsbl.org',);

# If Client IP is listed in MORE DNSBLS than this var,it gets REJECTed immediately
$MAXDNSBLHITS  = 3;

# alternatively,if the score of DNSBLs is ABOVE this level,reject immediately
$MAXDNSBLSCORE = 9;

$MAXDNSBLMSG = '550 Az levelezoszerveruk IP cime tul sok spamlistan talahato,kerjuk ellenorizze! / Your MTA is listed in too many DNSBLs; please check.';

## RHSBL settings
@rhsbl_score = (
        'multi.surbl.org',4,'multi.surbl.org','rhsbl.ahbl.org','dsn.rfc-ignorant.org',#       'postmaster.rfc-ignorant.org',0.1,'postmaster.rfc-ignorant.org',#       'abuse.rfc-ignorant.org','abuse.rfc-ignorant.org'
);

# skip a RBL if this RBL had this many continuous errors
$BL_ERROR_SKIP = 2;

# skip a RBL for that many times
$BL_SKIP_RELEASE = 10;

## cache stuff
# must be a directory (add trailing slash)
$LOCKPATH = '/var/run/policyd-weight/';

# socket path for the cache daemon.
$SPATH = $LOCKPATH.'/polw.sock';

# how many seconds the cache may be idle before starting maintenance routines
#NOTE: standard maintenance jobs happen regardless of this setting.
$MAXIDLECACHE = 60;

# after this number of requests do following maintenance jobs: checking for config changes
$MAINTENANCE_LEVEL = 5;

# negative (i.e. SPAM) result cache settings ##################################

# set to 0 to disable caching for spam results. To this level the cache will be cleaned.
$CACHESIZE = 2000;

# at this number of entries cleanup takes place
$CACHEMAXSIZE = 4000;

$CACHEREJECTMSG  = '550 temporarily blocked because of previous errors';

# after NTTL retries the cache entry is deleted
$NTTL = 1;

# client MUST NOT retry within this seconds in order to decrease TTL counter
$NTIME = 30;

# positve (i.,e. HAM) result cache settings ###################################

# set to 0 to disable caching of HAM. To this number of entries the cache will be cleaned
$POSCACHESIZE = 1000;

# at this number of entries cleanup takes place
$POSCACHEMAXSIZE = 2000;

$POSCACHEMSG = 'using cached result';

#after PTTL requests the HAM entry must succeed one time the RBL checks again
$PTTL = 60;

# after $PTIME in HAM Cache the client must pass one time the RBL checks again.
#Values must be nonfractal. Accepted time-units: s,m,h,d
$PTIME = '3h';

# The client must pass this time the RBL checks in order to be listed as hard-HAM
# After this time the client will pass immediately for PTTL within PTIME
$TEMP_PTIME = '1d';


## DNS settings

# Retries for ONE DNS-Lookup
$DNS_RETRIES = 1;

# Retry-interval for ONE DNS-Lookup
$DNS_RETRY_IVAL  = 5;

# max error count for unresponded queries in a complete policy query
$MAXDNSERR = 3;

$MAXDNSERRMSG = 'passed - too many local DNS-errors';

# persistent udp connection for DNS queries.
#broken in Net::DNS version 0.51. Works with Net::DNS 0.53; DEFAULT: off
$PUDP= 0;

# Force the usage of Net::DNS for RBL lookups.
# Normally policyd-weight tries to use a faster RBL lookup routine instead of Net::DNS
$USE_NET_DNS  = 0;

# A list of space separated NS IPs
# This overrides resolv.conf settings
# Example: $NS = '1.2.3.4 1.2.3.5';
# DEFAULT: empty
$NS  = '';

# timeout for receiving from cache instance
$IPC_TIMEOUT  = 2;

# If set to 1 policyd-weight closes connections to smtpd clients in order to avoid too many
#established connections to one policyd-weight child
$TRY_BALANCE  = 0;

# scores for checks,WARNING: they may manipulate eachother
# or be factors for other scores.
#  HIT score,MISS Score
@client_ip_eq_helo_score = (1.5,-1.25 );
@helo_score  = (1.5,-2 );
@helo_score  = (0,-2 );
@helo_from_mx_eq_ip_score= (1.5,-3.1  );
@helo_numeric_score= (2.5,0 );
@from_match_regex_verified_helo= (1,-2 );
@from_match_regex_unverified_helo = (1.6,-1.5  );
@from_match_regex_failed_helo  = (2.5,0 );
@helo_seems_dialup = (1.5,0 );
@failed_helo_seems_dialup= (2,0 );
@helo_ip_in_client_subnet= (0,-1.2  );
@helo_ip_in_cl16_subnet  = (0,-0.41 );
#@client_seems_dialup_score  = (3.75,0 );
@client_seems_dialup_score  = (0,0 );
@from_multiparted  = (1.09,0 );
@from_anon= (1.17,0 );
@bogus_mx_score = (2.1,0 );
@random_sender_score  = (0.25,0 );
@rhsbl_penalty_score  = (3.1,0 );
@enforce_dyndns_score = (3,0 );

spamassassin / init.pre(我把.pre文件放在一起)

loadplugin Mail::SpamAssassin::Plugin::Hashcash
loadplugin Mail::SpamAssassin::Plugin::SPF
loadplugin Mail::SpamAssassin::Plugin::Pyzor
loadplugin Mail::SpamAssassin::Plugin::Razor2
loadplugin Mail::SpamAssassin::Plugin::AutoLearnThreshold
loadplugin Mail::SpamAssassin::Plugin::MIMEHeader
loadplugin Mail::SpamAssassin::Plugin::ReplaceTags
loadplugin Mail::SpamAssassin::Plugin::Check
loadplugin Mail::SpamAssassin::Plugin::HTTPSMismatch
loadplugin Mail::SpamAssassin::Plugin::URIDetail    
loadplugin Mail::SpamAssassin::Plugin::Bayes
loadplugin Mail::SpamAssassin::Plugin::BodyEval
loadplugin Mail::SpamAssassin::Plugin::DNSEval
loadplugin Mail::SpamAssassin::Plugin::HTMLEval
loadplugin Mail::SpamAssassin::Plugin::HeaderEval
loadplugin Mail::SpamAssassin::Plugin::MIMEEval
loadplugin Mail::SpamAssassin::Plugin::RelayEval
loadplugin Mail::SpamAssassin::Plugin::URIEval
loadplugin Mail::SpamAssassin::Plugin::WLBLEval
loadplugin Mail::SpamAssassin::Plugin::VBounce
loadplugin Mail::SpamAssassin::Plugin::Rule2XSBody

spamassassin / local.cf(parts)

use_bayes                       1
bayes_auto_learn                1
bayes_store_module              Mail::SpamAssassin::BayesStore::MySQL
bayes_sql_dsn                   DBI:mysql:db:127.0.0.1:3306
bayes_sql_username              user
bayes_sql_password              pass
bayes_ignore_header             X-Bogosity
bayes_ignore_header             X-Spam-Flag
bayes_ignore_header             X-Spam-Status

### User settings
user_scores_dsn                 DBI:mysql:db:127.0.0.1:3306
user_scores_sql_password        user
user_scores_sql_username        pass
user_scores_sql_custom_query    SELECT preference,value FROM _TABLE_ WHERE username = _USERNAME_ OR username = '$GLOBAL' OR username = CONCAT('%',_DOMAIN_) ORDER BY username ASC

# for better speed
score DNS_FROM_AHBL_RHSBL       0
score __RFC_IGNORANT_ENVFROM    0
score DNS_FROM_RFC_DSN          0
score DNS_FROM_RFC_BOGUSMX      0
score __DNS_FROM_RFC_POST       0
score __DNS_FROM_RFC_ABUSE      0
score __DNS_FROM_RFC_WHOIS      0

更新01

由于adaptr建议我删除policyd-weight并配置postfix postscreen,这导致RAM使用率约为-15-20 MB,工作速度更快.我不确定它是否满负荷工作,但似乎很有希望.